喷水法驯食幼蛙效果好

喷水法驯食幼蛙效果好经过变态后发育而成的幼蛙嗜食动物性活饵，在规模化、集约化养殖牛蛙的条件下，如果单纯投喂活饵，不但饵源有限，而且费工时、成本高。所以，如何驯化幼蛙摄食人工饵料成为众多养蛙者所关注的问题。笔者依据牛蛙摄食特性，通过实践，摸索出喷水驯食...     

网箱主养草鱼高产技术研究

进行了水库网箱养草鱼不同放差规格,密度,饵料种类投喂方法,鱼病防治等综合技术研究。总面积７５ｍ＾２的网箱共产草鱼６０２７ｋｇ,净产５４６１．６ｋｇ,平均８０．３６ｋｇ／ｍ＾３,试验证明：网箱主养鱼在北方地区是可行的,合理调整青饲料与配饵的搭配比例,以促进草鱼生长,提高产量放养鱼种最适密度为４０－６０尾／ｍ＾２,规格在３５ｇ／尾以下的鱼种不宜网箱养殖。     

一种简便效好的幼蛙驯食法

一种简便效好的幼蛙驯食法经过变态后发育而成的幼蛙嗜食动物性活饵，在规模化、集约化养殖牛蛙的条件下，如果单纯投喂活饵，不但饵源有限，而且费工时、成本高。随着牛蛙养殖业的不断发展，如何短快好省驯化幼蛙摄食人工饵料，成了众多养蛙者所关注的热点问题。笔者依据...     

鳄龟高产生产态养殖技术研究

在攀藤植物瓜菜架绿荫下,利用室外自然水温,施用微生态调节剂ＰＳＢ,投喂不含激素及禁用药物的龟专用全价配合饵料,合理调控水质等技术,对平均规格１８６．６ｇ／只,放养密度４５２３．５ｇ／ｍ＾２、２４只／ｍ＾２的幼鳄龟做生态养殖试验,经１１６ｄ的养殖,平均规格达５７４ｇ／只,净单产９．３９ｋｇ／ｍ＾２;以养龟废水浇灌瓜菜,收获瓜菜２０ｋｇ／ｍ＾２。整个养殖期间,均无“三废”;所产鳄龟及瓜菜当属绿色食品。     

网箱养殖淡水鲳试验

为探索网箱养殖淡水白鲳的可行性，对网箱养殖淡水鲳的鱼种放养规格，密度，防逃措施等进行了试验。阶段验收结果：净产鱼１５６．９ｋｇ／ｍ＾２，盈利１００６．６元／ｍ２＾２，平均体重５７８ｇ／尾，增重８．３倍，投入产出比１：１．８９。     

控温快速养殖中华鳖技术的研究

利用玻璃温室采光加温和塑料大棚采光增温两种方式,分别在越冬前和越冬后进行稚鳖和幼鳖养殖,投喂全价配合饲料,结果：稚鳖经１００天的饲养,平均体重从３—５ｇ长到７２．２５ｇ,平均日增重０．６８ｇ／只,饵料系数为１．３０,成活率９４．６６％,单产为１．２９ｋｇ／ｍ２,幼鳖经７３天饲养,平均体重从７２．２５ｇ长到２５１．５７ｇ,平均日增重为２．４６ｇ／只,饵料系数１．２６,成活率９７．３２％,单产３．１２ｋｇ／ｍ２。此种养殖方式,为北方地区人工快速养鳖,探索了一条有效途径。     

幼蛙饲养及驯食技术

幼蛙饲养是牛蛙养殖中的关键一环 ,现将其饲养要点和驯食方法介绍如下。１幼蛙池的建造１．１场地选择要求选择环境安静、水源充足、排灌水方便、无工农业污染、温暖、背风向阳的地方。１．２池塘建造面积８０～１００ 为宜 ,池堤坡度１∶２．５ ,池深０．８～１ｍ ,有排灌水管道。幼蛙池可建大、中、小３种 ,以便视幼蛙生长发育情况随时调整 ,实行分级饲养 ,避免以强凌弱 ,以大吃小。１．３围墙建造要求墙高１．５～２ｍ ,墙壁光滑、圆角 ,“Ｔ”型或“Ｙ”型檐 ,刷成灰色。（不宜用红绿等耀眼色彩）。也可用铁丝网、尼龙网、石棉瓦等将池…     

生态因子对条斑紫菜自由丝状体生长的影响

报道了生态因子对条斑紫菜自由丝状体生长的影响,结果表明,条斑紫菜自由丝状体生长的最适宜盐度范围为２０￣３０,低于１０的盐度不能生长,最适宜温度范围为１５℃￣２５℃,高限为３０℃,适宜光辐射照度１５μＥｍ％－２Ｓ＾－１￣６０μＥｍ＾２Ｓ＾－１,添加的适宜Ｎ浓度２０ｇ／ｍ＾３￣６０ｇ／ｍ＾３,Ｐ为１．５ｇ／ｍ＾３￣５ｇ／ｍ＾３。     

网箱培育牛蛙苗种技术

近年来，笔经反复试验探索，掌握了利用网箱进行牛蛙蛙卵孵化、蝌蚪培育、幼蛙驯食等牛蛙苗种培育技术，作为池塘鱼蛙立体养殖的配套技术，于2003年进行生产性应用，取得良好的效果。现将主要技术方法介绍如下。     

池养美蛙巧渡变态驯食关

美蛙的天然食性是吃活饵,但人工规模养殖,难以采集到大批量活饵,因此,美蛙蝌蚪变态为幼蛙后,必须驯养其摄食膨化颗粒饲料,并尽量缩短驯食期。据我地经验,驯食应抓住两个要点;一是要将变态蛙撵上食台,二是驯养其摄食人工饲料。基本操作方法如下: 1.科学修建幼蛙驯食池。长方形池为好,长宽比2—3:1。面积为10平方米至15平方米,泥底。池埂为水泥抹面的硬埂,或为拌有5％生石     

Changes of Fatty Acid Composition in Frog Legs (Rana esculenta) During Cold Storage Period: Irradiation Effect

This study investigates the changes in fatty acid profile of gamma irradiated frog legs (Rana esculenta) during cold (2°C) storage period. Instead of freezing the frog legs for a prolonged shelf life, gamma irradiated fresh frog legs can be used for consumer satisfaction, because consumers prefer fresh frog legs and are willing to pay more than for frozen in the European market. Frog legs were irradiated at doses of 0, 4, and 5 kGy using ⁶⁰Co sources. The main fatty acids of nonirradiated and irradiated frog legs (4 and 5 kGy) were palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1ω9), linoleic acid (C18:2ω6), and eicosatrienoic acid (C20: 3ω3, ETE). Low doses (4 and 5 kGy) of irradiation treatment had no effect on fatty acid components of frog legs compared to the nonirradiated ones (p > 0.05). The fatty acid composition of frog meat was characterized by its high linoleic acid content (17.1–21.4%). At the initial stage of the storage, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels of frog legs remained unchanged with low doses of irradiation (p < 0.05). These fatty acids decreased significantly in the irradiated group (p < 0.05) at the end of the storage period. However, there were no significant changes in nonirradiated frog legs after 10 days of storage.     

林蛙肠道中乳酸菌的分离及鉴定

用2种方法从健康林蛙肠道菌群中分离乳酸菌,并进一步纯化及鉴定.试验结果表明,用乳酸菌半选择性培养基液体培养液先富集后分离得到了11株单一的乳酸杆菌,经过一系列生化鉴定,11株菌为同一种菌即嗜酸乳杆菌.该菌对嗜水气单胞菌具有抑制作用,抑菌圈直径为12 mm.在胆盐含量为0.3%,pH值为3时仍然生长,表明该菌株完全能适应动物胃肠道环境,作为微生态制剂用菌种具有较好的潜力.     

黄河三角洲稻田养殖牛蛙试验

在３亩稻田中进行了牛蛙、水稻生态养殖、不投饵、不施农药、经９２天养成，平均亩产商品牛蛙１０１．８ｋｇ，亩产水稻４８９．８ｋｇ，每亩盈利１６２３元。１９９４年９月专家鉴定认为：本研究属国内领先水平。     

黑鲪工厂化育苗技术研究

研究了亲鱼选择、暂养和苗种的饵料转换、日常管理和病害防治等一套工艺流程，在３００ｍ３育苗水体中，育出２６．７ｍｍ以上黑鲪鱼苗３２．１５万尾，鱼苗培育成活率３３．５％。专家鉴定认为，本成果总体达国内先进水平，其中产仔率、单位水体出苗量等方面属国内领先。     

Comparison of ozone,hydrogen peroxide and removal of infected eggs for prevention of fungal infection in sturgeon hatchery

ABSTRACT:   The objective of this study was to evaluate the effects of ozone, hydrogen peroxide and removal of infected eggs (five times per day) on prevention of fungal infection on Iranian sturgeon Acipenser persicus . The effects of 0.05, 0.1 and 0.15 p.p.m. of ozone, and 500 and 1000 p.p.m. of hydrogen peroxide in two different egg disinfection procedures (with and without removal of infected eggs) were examined on hatching ratio. Egg disinfection by 1000 p.p.m. hydrogen peroxide (with removal of infected eggs) resulted in the greatest hatching ratio (78%) among all treatments. Among ozone treatments, 0.15 p.p.m. (with removal of infected eggs) showed the highest hatching ratio (76.4%). The hatching ratio of the control group (without disinfectant and removal of infected eggs) was 34.4%. Removal of infected eggs increased the hatching ratio by 16.1% compared to treatments without infected egg removal, and there was a significant difference ( P  < 0.01). Ozone is preferred to hydrogen peroxide because a lower concentration of ozone is required to disinfect the culture medium; consequently, environmental pollution will be decreased. A low correlation ( r  = −0.35) was observed between hatchery water temperature and fungal infection percentage in the control.     

人工环境下棘腹蛙(Paa boulengeri)非繁殖期摄食行为的研究

2009年9月26日—10月6日对人工养殖环境棘腹蛙(Paa boulengeri)非繁殖期摄食行为进行了观察。结果显示:非繁殖期,棘腹蛙幼蛙早于成蛙出来觅食,雄蛙早于雌蛙出来觅食;棘腹蛙摄食高峰期出现在19:00—20:00。在整个摄食过程中,棘腹蛙的行为可划分为静止、跳跃、转向、捕食、侵占、驱赶、打斗、爬行。棘腹蛙幼蛙与成蛙、雌性成蛙与雄性成蛙之间在摄食行为上存在差异,其中幼蛙与成蛙之间在跳跃、转动、捕食、侵占、驱赶、打斗行为上存在显著差异(P<0.05);成年雌蛙与雄蛙之间在侵占、驱赶、打斗行为上存在显著的差异(P<0.05)。     

Inducing oocyte maturation, ovulation and spawning in the African catfish, Heterobranchus longifilis Valenciennes (Pisces: Clariidae), using frog pituitary extract

Abstract. Oocyte maturation, ovulation and spawning were successfully achieved in the African catfish, Heterobranchus longifilis Valenciennes, using frog pituitary extract. During artificial spawning, oocyte maturation and ovulation were induced at a dosage of 7mg per kg of individual fish weight. Latency period varied from 7 h at 29°C to 11 h at 25°C. Dead eggs became opaque between 8 and 10h after fertilization while embryogenesis was found to be temperature dependent. Mean hatching and larval deformity rates were 63·08%± 7·56 and 8·08%± 1·93 respectively. During induced natural spawning, the extract was applied at a dosage of 35 mg per kg of female fish weight. Spawning occurred between 10 and 11 h after hypophysation. Mean hatching and larval deformity rates were 41·38%± 8·48 and 10·00%± 2·00 respectively.     

大鲵人工繁殖技术初步研究

利用长200m、宽5．2m、高4．5m的山洞,在6m^2和0．48m^2的养殖池中用石板材和鹅卵石搭设人工洞穴,以人工养殖的Ⅴ-Ⅶ龄的子二代大鲵作为亲体开展人工繁殖研究。亲鲵培育水温19．0～20．5℃,pH7．2—7．3,DO5．8～7．4mg／L,光照〈300Lux;催产选择在7月上旬进行。激素选用LRH-A2＋HCG,剂量LRH—A2 10-20ug／kg＋HCG1000～2000IU／kg,雌雄同剂量。一次性腹腔注射;受精卵孵化温度18～18．5℃,pH7．2～7．3,DO6．0—8．0mg／L,光照〈100Lux。2010年7月催产雌鲵26尾,雄鲵24尾,催产后第4d,4尾雌鲵产卵3800粒,获受精卵962粒,受精率25．32％。受精卵经35—38d的孵化,共孵出稚鲵172尾,孵化率为17．88％。     

密斯特黄彩鲶仔、稚、幼鱼的生长与发育研究

在水温22～24℃,pH7.0左右的人工培育条件下,对密斯特黄彩鲶(Mystus sp.)仔、稚、幼鱼的形态特征和生长发育进行了观察与研究。密斯特黄彩鲶的鱼苗发育分为卵黄囊期仔鱼期(初孵至第5天)、晚期仔鱼期(第6～10天)、稚鱼期(第11～20天)和幼鱼期(第20天以后)。初孵仔鱼平均全长5.12 mm,卵黄囊体积1.63 mm3;仔鱼第3天开始摄食,第5天卵黄囊被完全吸收,鱼苗主要外部器官主要集中在晚期仔鱼阶期和稚鱼期内形成。仔鱼在饥饿状态下最高初次摄食率出现在出膜后第6天,为84.0%,其饥饿的不可逆点则为出膜后第8天,第8天以后即进入不可逆PNR期,至第11天绝大部分饥饿仔鱼死亡。     

Low salinity increases survival,body weight and development in tadpoles of the Chinese edible frog Hoplobatrachus rugulosus

Water salinity affects survival, growth and metamorphosis of anuran tadpoles. Hoplobatrachus rugulosus is considered not only as a freshwater amphibian but is also found in brackish wetlands. However, whether salinity change interferes with hatching, survival, body mass and development of H. rugulosus tadpoles is unknown. We found that salinity levels of <4‰ did not affect of survival or hatching of H. rugulosus eggs. At an early larval stage, tadpoles could tolerate up to 9‰ salinity for 96 h; however, body water content decreased when salinity was >5‰. After a 3‐week experiment, body weights of tadpoles exposed to 2‰ and 4‰ salinities were higher but that of the 6‰ group was lower compared with the 0‰ group. More than 90% of tadpoles exposed to 2‰ and 4‰ salinity showed complete metamorphosis. Salinity levels <4‰ promoted survival of tadpoles better than 0‰, whereas none of tadpoles in the 6‰ group became juvenile frogs in 50 days. Time taken to reach metamorphosis was shorter for 2‰ and 4‰ (47.22 ± 0.28 and 47.26 ± 0.33 days, respectively) than for 0‰ (49.31 ± 0.35 days). Juvenile frogs in the 2‰ group had greater body weight than the control. It could be concluded that salinity of <4‰ increased survival and body weight of H. rugulosus tadpoles, and shortened the time taken to reach metamorphosis.